A single variable.
In an experiment we are trying to figure out how one thing (independent) effects another thing (dependent) so we want to keep everything constant. We want that experiment to be controlled so nothing else is effecting our dependent variable. That way we can be 100% sure that any change to our dependent is due to our independent variable. Hope that makes sense
Answer: Hydrosphere is the total mass of water found on the Earth's surface. Atmosphere is the layer of air that envelopes the Earth. Hydrosphere consists of lakes, oceans, rivers, seas, water vapours, underground water and ice sheets of the mountainous regions.
Explanation:
Mudflows are called lahars.
B. the units are based on multiples of 10
this is true because when you convert it makes conversion a lot easier then if you are not using the metric system